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ISS 3, SECTION 5 1 8-450- 1 00
TABLE
0
(Conti
TROUBLE ANALYSIS TABLE
TROUBLE
POSSIBLE CAUSE
POSSIBLE SOLUTION
Incorrect
a.
Y3 relay in selector (424B/424C KTU )
Check that CGO-CGl strap is removed.
intercom codes
is not dropping.
See Fig. 50.
are dialed when
using DSS con-
sole.
a.
478B or 440A KTU is not plugged in
Check that KTU is properly seated in
Cannot dial on
correctly.
connector and is located in the right
intercom.
On
connector.
See Fig. 6 and 59.
going off-hook,
b.
Rotary dial system with CG-RSl
Check CG-RSl strap. See Fig. 3 or 60.
calling station
strap missing.
hears tone burst.
c.
If DSS console is provided, connec-
Check DSS console cutdown.
Check
tions may be bad.
that console is properly plugged in.
Hold lamp on
a.
Attendant set is not modified or
Disable hold lamp at attendant's set
attendant's set
is improperly modified.
(3.13).
is always lit.
a.
451A/451B KTU is not plugged in
Check that KTU is properly seated in con-
properly.
nectar and is located in the right con-
nectar.
See Fig. 6 and 37.
No music-
on-hold or
b.
Music source volume too low.
Gradually increase volume while listening.
distorted
See 4.37.
music-on-
c.
Music source unable to drive the
Source must be approx. 8 ohms or less.
hold.
451A KTU.
d.
Blown fuse or improperly
Check fuses in 33A and verify wiring.
wired 33A voice coupler.
a.
Volume control turned off or
Turn on or adjust volume control.
Low or no
set too low.
volume on
b.
Defective volume
Replace telephone set.
ringing or
voice
control.
signaling.
c.
Defective speaker.
Replace speaker.
False hold
a.
Incorrect sequence of BD
Replace key or replace telephone set.
condition when
contact on line key.
changing lines
or lightly
touching
line buttons.
Low output
a.
20A-49 potentiometer
Adjust potentiometer on 20A-49
from paging
set too low.
apparatus unit.
speaker.
b.
Wrong speakers used.
Use only 45-ohm speakers.
Page 85